I've got a question about the alternator on a '88 full size Chevy truck (not my Blazer). It's making a lot of noise, and I'm wondering, when an alternator goes out, are there any warning signs? Or do they just go out? I suspect it might be the bearings, it has a loose pulley type noise. I haven't tested it yet, either by disconnecting the battery while it's running or by removing it and having it bench tested. What about a rebuild kit? Would they sell just the bearings? BTW I replaced the serpentine belt two weeks ago, everything seemed fine. I didn't over-tighten it, it might actually be a little loose as the adjuster pulley maxed out a little too early. Thanks! It's not what you buy, it's what you build!